Common Fuel Injector Failures: Signs, Cleanliness, And More!
Although fuel injection dates back to the 1950s in production cars, the technology didn’t become commonplace until the late 1980s. Today, all new vehicles have electronic fuel injection instead of a carburetor. This technology uses individual injectors to supply fuel to the engine.
Fuel injection is much more efficient and reliable than a carburetor. But, like any automotive part, fuel injectors can end up failing, causing some noticeable symptoms. You should be on the lookout for this part, discover here everything about common fuel injector failures , we will help you here to identify the problem before it is too late.
Function of the fuel injectors
Most fuel injectors are simple, electronically operated devices. The engine computer, often referred to as the powertrain control module (PCM), activates each of the injectors to spray fuel into the engine’s cylinders.
A typical fuel injector contains an electronic solenoid and a spring-loaded valve . The PCM activates the solenoid, which, in turn, lifts the valve off its seat, allowing fuel to enter the cylinder.
There are two common types of modern electronic fuel injection: port injection and direct injection. In a port injection system, the injectors are located in the intake manifold, where they spray fuel into the intake ports. In contrast, in a direct injection system, the injectors are located in the cylinder head of the engine, where they spray fuel directly into the combustion chamber.
Most vehicles have one injector per cylinder . However, there are some applications that have two injectors per cylinder: one for the port injection system and one for the direct injection system. There is also an older type of fuel injection technology, called throttle body injection, which uses only one or two throttle body mounted fuel injectors.
Signs and common failures of fuel injectors
Although fuel injectors are quite robust, over time they can fail mechanically or electrically. A clogged or stuck injector will cause the engine to run low on fuel. On the other hand, an injector with internal leaks or stuck inside will cause the engine to run rich (with too much fuel).
When one or more of the injectors fail, you will likely notice at least one of the following common fuel injector failures:
1- Misfires and irregular operation
Your car’s engine must receive the proper amount of air and fuel for complete combustion. A bad injector can cause the engine to run too little or too much fuel (depending on how the injector failed), resulting in incomplete combustion, also known as a misfire. As a driver, you will notice that misfiring causes the vehicle to run rough or hesitate.
2- Engine light illuminates
The PCM monitors the injectors and their circuits while continually looking for engine misfiring. If the module detects a misfire or injector circuit problem, it will turn on the check engine light and store a Diagnostic Trouble Code (DTC) in memory.
3- Abnormal odors
An injector that sticks open can allow unburned fuel to pass through the engine. From there, fuel enters the catalytic converter, causing the device to overheat and create a rotten egg smell (a problem that will eventually damage the catalytic converter).
Also, in some cases, injector leaks can cause a noticeable fuel odor. In some extreme cases, a clogged direct injector can even allow raw, stinky fuel to pass through the engine and out the car’s tailpipe.
4- Black smoke in the exhaust pipe
The PCM can compensate for a rich running condition to a certain extent. But if one or more of the injectors is leaking a substantial amount of fuel into the engine, the vehicle will run rich enough to produce black smoke from the tailpipe.
5- Oil dilution
If one or more injectors leak on the engine, fuel can pass past the piston rings and into the crankcase, where it mixes with the engine oil. In cases where the problem is severe enough, the oil level may appear overfilled on the dipstick.
Engines that have direct fuel injection tend to be the most susceptible to oil dilution. If the problem is not fixed quickly, serious engine damage can occur.
6- Increased fuel consumption
Obviously, a leaking injector wastes fuel. However, what you may not know is that anything that causes a misfire (including one or more stuck closed injectors) will also result in increased fuel consumption. In other words: You are likely to see a decrease in fuel economy, regardless of whether the faulty injector(s) are causing the engine to run lean or rich. This is a notorious common fuel injector failure.
Should I clean the fuel injectors?
Some experts recommend cleaning your car’s injectors every 25,000 (40 thousand kilometers) to 30,000 miles (48 thousand kilometers). Although some might say this is an exaggeration, there are definite benefits to cleaning dirty fuel injectors, one of which is that you can save yourself from having to change one or more of the injectors.
There are two main methods of cleaning injectors. The first is the in-car method, which usually involves using pressurized equipment to run solvent through the injectors. There is also an off-car procedure, in which the technician removes the injectors from the engine and places them in a specific cleaning machine. Cleaning the injectors outside the car provides the best results , but it is also the more expensive of the two methods.
Also, there are bottles of fuel injector cleaner that you can pour into the gas tank. Some professionals swear by these products, while others feel they don’t do enough on their own without a thorough injector cleaning.
Fuel Injector Cleaning Cost Vs. Replacement cost
Cleaning the injectors is almost always less expensive than replacing them . But there are many cases in which a simple cleaning does not solve the problem, and the injectors must be changed.
For a car injector cleaning, you can generally expect to pay between $100 and $250. Although to replace a single injector, most shops will charge between $150 and $500.
Regardless of whether you clean or replace the injectors, the exact cost of the repair will depend on several factors, starting with the year, make and model of your vehicle. Of course, if you have the necessary knowledge, you can save a lot of money by replacing the injectors yourself.
